During execution of a software application, such as a client-server application or a web application, a server may send one or more instructions to a client that are to be executed by a client application (e.g., a web browser) executing on a device. For example, the server may send one or more client-side scripts in a scripting language (e.g., JavaScript) that are to be executed by the client application in order to make the software application more interactive (e.g., to support dynamic Hyper Text Markup Language (DHTML)). Although such instructions may be embedded within a document (e.g., an HTML document) that is generated dynamically by the server upon execution of a server-side script, the instructions themselves may pertain to features of the application that are not appropriate for the device (e.g., that require a capability that the device does not possess) or that are not appropriate for the user of the device (e.g., that a user does not wish to use). In such cases, the client application may conditionally execute portions of the instructions (e.g., via if/then statements within the instructions). Thus, including the remaining portions of the instructions may be an inefficient use of resources.